Subject: [Dots] Suresh Krishnan's Discuss on draft-ietf-dots-signal-channel-31: (with DISCUSS and COMMENT)

From: Suresh Krishnan via Datatracker <[email-masked]>
Date: Tue, 30 Apr 2019 20:06:56 -0700

Suresh Krishnan has entered the following ballot position for
draft-ietf-dots-signal-channel-31: Discuss

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DISCUSS:
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This should be easy to clear up, but I would like to understand why this
document needs to restate the motivation and describe the algorithm for happy
eyeballs instead of simply stating that hosts should use RFC8305 and then
specify that UDP must be tried before TCP in each of the address families. If
you do want to specify the whole algorithm here it needs to be more specific
than "in a manner similar to the Happy Eyeballs mechanism" as it is not clear
where it is similar (and where it will differ). It also looks like the example
flow in Figure 4 is not consistent with the description before (TCP+IPv6 before
UDP+IPv4)

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COMMENT:
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* Section 7.3

This text is wrong and needs to be removed

"IP packets whose size does not exceed 576 bytes should never need to be fragmented"

RFC791 only requires all hosts to be prepared to accept datagrams of up to 576 octets.